Lighting control systems automate the operation of lighting within a building or residence based upon, for example, preset time schedules and/or occupancy and/or daylight sensing. The Lighting systems typically employ occupancy sensors and/or daylight sensors to determine which lighting devices to activate, deactivate, or adjust the light level of, and when to do so. Occupancy sensors typically sense the presence of one or more persons within a defined area and generate signals indicative of that presence. Daylight sensors typically sense the amount of daylight present within a defined area and generate signals indicative of that amount. Typically, lighting systems receive the sensor signals at a central lighting controller.
The lighting systems are advantageous because they typically reduce energy costs by automatically lowering light levels or turning off devices and appliances when not needed, and they can allow all devices in the system to be controlled from one location.
Centrally controlled lighting systems can be disadvantageous because all decision making occurs at the controller. Therefore, if the controller becomes inoperative, all lighting devices in the system are no longer under automated control and some or all may not operate even manually. Similarly, if a connection to or from the controller is severed, the lighting devices served by that connection are no longer under automated control and also may not operate manually. Partial or system-wide functional changes, such as an immediate need to override current system settings (for example, during a fire or other emergency), cannot be made from anywhere but the controller.
It is desirable to have a method, system and apparatus for providing lighting devices that are independently controllable.